Hydrophobically modified water-soluble polymers of various types have been used to thicken latex paints to provide a certain performance during manufacturing, storage, and applications. Some of these properties include: ease of formulation, pigment settling prevention, film build during application, spatter resistance, low sag, good flow, and leveling of the paint film. These water-soluble polymers may come from a natural source like cellulose, starch, polydextran, guar gum or their ionic and non-ionic derivatives (hydroxy ethyl, hydroxypropyl). Some examples of synthetic water-soluble polymers are the polyacrylamides, polyacrylates, polyvinyl alcohol, polyvinyl sulfonates, polyethylene imine, polydadmac, polyamideazetidinium ion, polyvinylpyrolidone, polyaspartates, polyacetalpolyether, polyalkylethers, and polyalkylthioethers. Most of the water soluble polymer types are described in “Water soluble polymers” by Yale Meltzer (Noyes Data Corporation, Parkridge, N.J., USA, 1981).
The hydrophobe attachment is usually done with a single alkyl group or an alkyl phenol ethoxylate bearing a halide or an epoxide. There are also examples where the hydrophobe is bunched together before the attachment as in U.S. Pat. No. 4,426,485, USP application 0045724 A1 (2002), U.S. Pat. No. 5,292,828, and U.S. Pat. No. 6,337,366. In these patents, the hydrophobes are pre-connected with each other via a connecting reagent such as diisocyanate, diepoxide, epichlorohydrin or a primary amine.